Prefabrication is recognised as an appropriate solution to overcome several problems in
construction such as low productivity, high waste production, inferior working conditions and
insufficient quality. Even though prefabrication offers many benefits, significant number of
inefficiencies could be identified from its production process. Lean Production Principles are
recognised as a paramount concept, which enables to address such production process related
inefficiencies. This study aims to investigate how application of Lean principles help to mitigate
inefficiencies in Prefabrication Production Process (PrefabPP) and thereby learn how such an
application leads to sustainability. Observations and semi-structured, interviews were conducted to collect data within selected three case studies in Sri Lanka (prefabrication production yards)
targeting executive level professionals who engaged in 'prefabrication bridge beam production
The collected data were analysed using code-based content analysis and mapped using
tables and matrices. Findings revealed several inefficiency issues in PrefabPP which were highly
moderately severe and less severe. The study revealed that by adopting lean principles into
process. severe, PrefabPP that it will offer several key benefits to PrefabPP and its customers. Moreover, the results indicated that the application of Lean Production Principles to PrefabPP offers long-term benefits to construction by contributing towards sustainability. Thereby study offers some useful implications to prefabrication companies, construction professionals, researches and those who deal with sustainability issues